That part was clear :)

What still isn't clear to me is how exactly that "workflow" demo (and consequently the "money-shot" final generated images) happened.

There is a progression of generated images with increasing quality. Who did which steps in those iterations?

Blog post uses ambiguous language: "N-th image tries / removes / fixes", etc.

It's not clear though if it was:

1) algorithm steps (keep computing more till generated image looks good), or

2) human being tweaking inputs to fixed algorithm (keep painting new input/output doodles till generated image looks good), or

3) human being tweaking algorithm itself (change code till generated image looks good).